The present invention relates generally to telephone call screening. More particularly, the invention relates to a call screening system and method that uses speaker verification and/or speech recognition to ascertain the identity of a caller and thereafter handle the incoming call in a predetermined way based on the system user""s desires or usage profile.
Many people use caller ID to screen incoming calls. That is, they look at a screen display giving the identity of the callerxe2x80x94if the caller""s number is not blockedxe2x80x94before deciding whether to pick up the telephone or not. However, a high proportion of telephone numbers in North America is blocked, and in any case, a familiar caller may be calling from an unfamiliar number. In such case the familiar caller might be inadvertently rejected by the user.
There have been a number of proposed solutions to the problem, however each has proven deficient in certain important respects. One existing system is provided as a call screening service, typically a service that the user subscribes to at additional cost, in conjunction with the caller ID service. With this screening service, if the caller""s number is blocked, the system intercepts the call prior to ringing the user""s telephone. The caller is then prompted to state his or her name, or company affiliation, which are recorded as audio information, whereupon the call is then allowed to ring through to the user regardless of what the caller says. When the user answers the incoming call, rather than being immediately connected to the caller, the user is placed in communication with the call screening server. The server replays a prerecorded announcement that the incoming call was intercepted and then replays how the caller responded to the prompt for the caller""s name or company affiliation. The user then has the option to either (1) accept the incoming call, (2) reject the incoming call with a message to the caller that the call is refused or (3) reject the call with a message to the caller asking that the user be placed on the caller""s xe2x80x9cdo not callxe2x80x9d list.
While the aforementioned call screening system does give the user a means to avoid talking to unwanted callers, it still requires the user to pick up the telephone, listen to the call screening server""s message containing the incoming caller""s name or company affiliation and select one of the three call handling options. Thus, while this call screening system can eliminate the need to talk to unwanted callers, it does not insulate the user from having a tranquil evening spoiled by numerous calls by telemarketers. Although the user can select the parties with whom to speak, the telephone still rings.
Another proposed solution is the telemarketing call xe2x80x9czapperxe2x80x9d that screens out calls that are placed using predictive dialer computers. Some telemarketers will use predictive dialer computers to rapidly place calls, allowing them to spend time only on those calls where the party actually answers. The zapper emits a special tone that fools the dialing computer into thinking that the called number is disconnected or no longer in service. When the computer hears this tone it hangs up before the telemarketer is able to connect with the called party""s phone and the computer deletes the called party""s phone number from its database. In theory, over time, as the zapper-protected number is removed from more and more databases, the user experiences fewer and fewer telemarketing calls.
While interesting in theory, unfortunately, the zapper does not fully solve the call screening problem, because calls that are placed without use of predictive dialing computers or auto-dialer systems are not intercepted by the zapper.
The present invention affords considerable more functionality than either of the aforementioned call screening solutions. The present invention uses speaker verification and speaker recognition technology to construct an acceptable caller list, which is then used to screen incoming callers. In the presently preferred embodiment, when the user first signs up for the screening service based on the invention (or purchases a physical device in which the invention is incorporated), the system begins constructing speaker voice models for each of the people with whom the user carries out conversations of reasonable length. After each telephone call, the system will ask the user whether or not to enter the other person""s voice profile and telephone number (if unblocked) in the acceptable caller list. It may also prompt the user for the other person""s name.
Subsequently, if a person on the acceptable caller list calls the user back from the same unblocked number, the call will be put through immediately (as in the existing technology). On the other hand, if an acceptable caller calls from a blocked number or from a new number, the system will ask the caller for his or her name, and/or for other information. If the voice profile (possibly together with the name) matches the profile for someone on the acceptable caller list, the call will be put through; otherwise a message may be taken by routing the call to a suitable answering machine or voicemail system.
The invention can be implemented as either a server-based system or as a locally deployed hardware or software system associated with the user""s telephone equipment. The invention is also capable of being extended to more complex versions of the basic idea, in which there are several classes of callers and different actions to be taken for each. For instance, some callers might be subjected to a detailed series of questions by the system, with the resulting action determined by their recognized response. Also, the system can be configured to take other action based on who the caller is, or what the caller says. For example, the system can be configured so that the telephone system interface selectively communicates a message over a computer network, such as the internet.
As will be more fully explained herein, the invention offers a number of advantages over prior call screening systems. Calls from telemarketers and other unwelcome callers may be handled automatically by the system, based on rules established by the user. The invention allows the recipient of telephone calls to determine exactly how each class of call is to be handled, depending on the identity of the caller. Compared with existing systems, the invention has the advantage that calls from unwelcome people (e.g., telemarketers) do not consume any of the recipient""s time. For familiar, welcome callers using a blocked or unfamiliar number, the system imposes only a very slight delay (the time required for them to identify themselves to the system), rather than the longer delay imposed by other conventional systems which play back the response to the user. In effect, the invention gives users the capability to xe2x80x9chirexe2x80x9d an automatic secretary who will screen their calls and respond to them appropriately.
In accordance with one aspect of the invention, the call screener employs a telephone system interface having at least one port for connection to a telephone network, and at least one port for connection to the telephone device of a user. The interface is operable to selectively route calls (and refrain from routing calls) originating from the telephone network to the telephone device, or to another device, such as an answering machine or voice mail system. A dialogue system coupled to the telephone system interface elicits speech from an incoming caller and causes the telephone system interface to route calls from the incoming caller based on a comparison of the elicited speech with a set of stored speaker models.
The stored speaker models may be maintained automatically by the system, using either a passive mode, in which calls exceeding a predetermined duration are assumed to be xe2x80x9cacceptablexe2x80x9d callers; and a proactive mode in which the system prompts the user at the end of the call to elect whether to save the speech models developed during that call in the acceptable user database. If desired, the user can attach other attributes or special tags to the stored models, indicating special handling or call routing rules to be applied when that caller calls again.
For a more complete understanding of the invention, its objects and advantages, refer to the remaining specification and to the accompanying drawings.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.